From patchwork Thu Aug 22 21:15:32 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Detlev Casanova X-Patchwork-Id: 822035 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AEB7F1D278D; Thu, 22 Aug 2024 21:24:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724361898; cv=pass; b=bOTIP00Vg9RtWV906OPZSVaA/Bbg7XvwbQYhmOJjk79OBCyX3lR3ZuZm2yoEJEvXdO1b8l3TtgHPmtgv7QbLQ+hRGoV3aKxgQipvBEQQslr5jgtIVG6JVoCFDPX8SXJia6HgQQeAwElZdE6vcPmjCqyDK3KCbrbuGyD3FX8nfZE= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724361898; c=relaxed/simple; bh=zVTT7hS1BFwNpLoYhke/D3D2hjaA6JZjMoe9Hw23Zog=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BT7Pln5nAdWrD3JEK/d1VxjFdWwMB1a2NQXW+7+X6Wm9LgAs5Cpeovn4iNyQRHBiBoifPexmOvhR9i/Dzb4ZTPGNRqdF1U575EtSkaDDQ8AOCMamX8swiCMK7yR+YlYnlRmITe1iKE1ntEN5fFu+SUkZOwIzMqqFD8jyaH/h9+g= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=detlev.casanova@collabora.com header.b=PGR0EcSK; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=detlev.casanova@collabora.com header.b="PGR0EcSK" ARC-Seal: i=1; a=rsa-sha256; t=1724361876; cv=none; d=zohomail.com; s=zohoarc; b=FbD1jRP2lvK7yuhkPZwBvZaI/g2PJkXBYBfW9RY9SjpUjiDSRE3pCyxG7KWe2LmDVddL2ITDIghb6aoG6idGppwuN3mpuHttco9Qpv1Rv7QyXpw9jObmHejB4Avj8O77XoVNiGf+hI07/k0f5Jzw1oWSOrmd+O4Icif/aJKIrVA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1724361876; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=7YL5pWtXUp+PHdd3Kfu/uwF045nPBW8u8rSyR+5Ufm4=; b=bakPksguc+oW/3RVSPrvxhP3N+ZFYjGJlX86Iub89DpShq33wDCDf2hBM0XL2vr1vYVjOQUTCRMWUZWGm6Xupu1bi7Ju8NuJSM9vyCQU/GGfK7w0jCDgzYMvxE2r9icF3MEZO935VIVOO+0Nt8Af0yvZupm1RNA+KSIjSYWajhM= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=detlev.casanova@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1724361876; s=zohomail; d=collabora.com; i=detlev.casanova@collabora.com; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=7YL5pWtXUp+PHdd3Kfu/uwF045nPBW8u8rSyR+5Ufm4=; b=PGR0EcSKha34QXovj2e5Hguizkwl9uGTugPOm+BwTmun8q+IjegLnqS6RDyF3GxC gV5PKutb3vM17D9Gf4ocNZhTR5toolbkHD16k1tpTs6hAqrYA+1pOdz8+bqnbzElzry nqvSSPWB28yVXTZ+G54vteH7rwWv8Rj9isYa4NIU= Received: by mx.zohomail.com with SMTPS id 1724361876093426.5821241995659; Thu, 22 Aug 2024 14:24:36 -0700 (PDT) From: Detlev Casanova To: linux-kernel@vger.kernel.org Cc: Ulf Hansson , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Heiko Stuebner , Jaehoon Chung , linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, kernel@collabora.com, Shawn Lin , Detlev Casanova Subject: [PATCH v4 2/4] mmc: dw_mmc-rockchip: Add internal phase support Date: Thu, 22 Aug 2024 17:15:32 -0400 Message-ID: <20240822212418.982927-3-detlev.casanova@collabora.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240822212418.982927-1-detlev.casanova@collabora.com> References: <20240822212418.982927-1-detlev.casanova@collabora.com> Precedence: bulk X-Mailing-List: linux-mmc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ZohoMailClient: External From: Shawn Lin Some Rockchip devices put the phase settings into the dw_mmc controller. When the feature is present, the ciu-drive and ciu-sample clocks are not used and the phase configuration is done directly through the mmc controller. Signed-off-by: Shawn Lin Signed-off-by: Detlev Casanova Acked-by: Shawn Lin --- drivers/mmc/host/dw_mmc-rockchip.c | 171 +++++++++++++++++++++++++++-- 1 file changed, 160 insertions(+), 11 deletions(-) diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c index b07190ba4b7a..2748f9bf2691 100644 --- a/drivers/mmc/host/dw_mmc-rockchip.c +++ b/drivers/mmc/host/dw_mmc-rockchip.c @@ -15,7 +15,17 @@ #include "dw_mmc.h" #include "dw_mmc-pltfm.h" -#define RK3288_CLKGEN_DIV 2 +#define RK3288_CLKGEN_DIV 2 +#define SDMMC_TIMING_CON0 0x130 +#define SDMMC_TIMING_CON1 0x134 +#define ROCKCHIP_MMC_DELAY_SEL BIT(10) +#define ROCKCHIP_MMC_DEGREE_MASK 0x3 +#define ROCKCHIP_MMC_DEGREE_OFFSET 1 +#define ROCKCHIP_MMC_DELAYNUM_OFFSET 2 +#define ROCKCHIP_MMC_DELAYNUM_MASK (0xff << ROCKCHIP_MMC_DELAYNUM_OFFSET) +#define ROCKCHIP_MMC_DELAY_ELEMENT_PSEC 60 +#define HIWORD_UPDATE(val, mask, shift) \ + ((val) << (shift) | (mask) << ((shift) + 16)) static const unsigned int freqs[] = { 100000, 200000, 300000, 400000 }; @@ -24,8 +34,143 @@ struct dw_mci_rockchip_priv_data { struct clk *sample_clk; int default_sample_phase; int num_phases; + int internal_phase; }; +/* + * Each fine delay is between 44ps-77ps. Assume each fine delay is 60ps to + * simplify calculations. So 45degs could be anywhere between 33deg and 57.8deg. + */ +static int rockchip_mmc_get_internal_phase(struct dw_mci *host, bool sample) +{ + unsigned long rate = clk_get_rate(host->ciu_clk); + u32 raw_value; + u16 degrees; + u32 delay_num = 0; + + /* Constant signal, no measurable phase shift */ + if (!rate) + return 0; + + if (sample) + raw_value = mci_readl(host, TIMING_CON1); + else + raw_value = mci_readl(host, TIMING_CON0); + + raw_value >>= ROCKCHIP_MMC_DEGREE_OFFSET; + degrees = (raw_value & ROCKCHIP_MMC_DEGREE_MASK) * 90; + + if (raw_value & ROCKCHIP_MMC_DELAY_SEL) { + /* degrees/delaynum * 1000000 */ + unsigned long factor = (ROCKCHIP_MMC_DELAY_ELEMENT_PSEC / 10) * + 36 * (rate / 10000); + + delay_num = (raw_value & ROCKCHIP_MMC_DELAYNUM_MASK); + delay_num >>= ROCKCHIP_MMC_DELAYNUM_OFFSET; + degrees += DIV_ROUND_CLOSEST(delay_num * factor, 1000000); + } + + return degrees % 360; +} + +static int rockchip_mmc_get_phase(struct dw_mci *host, bool sample) +{ + struct dw_mci_rockchip_priv_data *priv = host->priv; + struct clk *clock = sample ? priv->sample_clk : priv->drv_clk; + + if (priv->internal_phase) + return rockchip_mmc_get_internal_phase(host, sample); + else + return clk_get_phase(clock); +} + +static int rockchip_mmc_set_internal_phase(struct dw_mci *host, bool sample, int degrees) +{ + unsigned long rate = clk_get_rate(host->ciu_clk); + u8 nineties, remainder; + u8 delay_num; + u32 raw_value; + u32 delay; + + /* + * The below calculation is based on the output clock from + * MMC host to the card, which expects the phase clock inherits + * the clock rate from its parent, namely the output clock + * provider of MMC host. However, things may go wrong if + * (1) It is orphan. + * (2) It is assigned to the wrong parent. + * + * This check help debug the case (1), which seems to be the + * most likely problem we often face and which makes it difficult + * for people to debug unstable mmc tuning results. + */ + if (!rate) { + dev_err(host->dev, "%s: invalid clk rate\n", __func__); + return -EINVAL; + } + + nineties = degrees / 90; + remainder = (degrees % 90); + + /* + * Due to the inexact nature of the "fine" delay, we might + * actually go non-monotonic. We don't go _too_ monotonic + * though, so we should be OK. Here are options of how we may + * work: + * + * Ideally we end up with: + * 1.0, 2.0, ..., 69.0, 70.0, ..., 89.0, 90.0 + * + * On one extreme (if delay is actually 44ps): + * .73, 1.5, ..., 50.6, 51.3, ..., 65.3, 90.0 + * The other (if delay is actually 77ps): + * 1.3, 2.6, ..., 88.6. 89.8, ..., 114.0, 90 + * + * It's possible we might make a delay that is up to 25 + * degrees off from what we think we're making. That's OK + * though because we should be REALLY far from any bad range. + */ + + /* + * Convert to delay; do a little extra work to make sure we + * don't overflow 32-bit / 64-bit numbers. + */ + delay = 10000000; /* PSECS_PER_SEC / 10000 / 10 */ + delay *= remainder; + delay = DIV_ROUND_CLOSEST(delay, + (rate / 1000) * 36 * + (ROCKCHIP_MMC_DELAY_ELEMENT_PSEC / 10)); + + delay_num = (u8) min_t(u32, delay, 255); + + raw_value = delay_num ? ROCKCHIP_MMC_DELAY_SEL : 0; + raw_value |= delay_num << ROCKCHIP_MMC_DELAYNUM_OFFSET; + raw_value |= nineties; + + if (sample) + mci_writel(host, TIMING_CON1, HIWORD_UPDATE(raw_value, 0x07ff, 1)); + else + mci_writel(host, TIMING_CON0, HIWORD_UPDATE(raw_value, 0x07ff, 1)); + + dev_dbg(host->dev, "set %s_phase(%d) delay_nums=%u actual_degrees=%d\n", + sample ? "sample" : "drv", degrees, delay_num, + rockchip_mmc_get_phase(host, sample) + ); + + return 0; +} + +static int rockchip_mmc_set_phase(struct dw_mci *host, bool sample, int degrees) +{ + struct dw_mci_rockchip_priv_data *priv = host->priv; + struct clk *clock = sample ? priv->sample_clk : priv->drv_clk; + + if (priv->internal_phase) + return rockchip_mmc_set_internal_phase(host, sample, degrees); + else + return clk_set_phase(clock, degrees); +} + static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) { struct dw_mci_rockchip_priv_data *priv = host->priv; @@ -64,7 +209,7 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) /* Make sure we use phases which we can enumerate with */ if (!IS_ERR(priv->sample_clk) && ios->timing <= MMC_TIMING_SD_HS) - clk_set_phase(priv->sample_clk, priv->default_sample_phase); + rockchip_mmc_set_phase(host, true, priv->default_sample_phase); /* * Set the drive phase offset based on speed mode to achieve hold times. @@ -127,7 +272,7 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) break; } - clk_set_phase(priv->drv_clk, phase); + rockchip_mmc_set_phase(host, false, phase); } } @@ -151,6 +296,7 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) int longest_range_len = -1; int longest_range = -1; int middle_phase; + int phase; if (IS_ERR(priv->sample_clk)) { dev_err(host->dev, "Tuning clock (sample_clk) not defined.\n"); @@ -164,8 +310,10 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) /* Try each phase and extract good ranges */ for (i = 0; i < priv->num_phases; ) { - clk_set_phase(priv->sample_clk, - TUNING_ITERATION_TO_PHASE(i, priv->num_phases)); + rockchip_mmc_set_phase(host, true, + TUNING_ITERATION_TO_PHASE( + i, + priv->num_phases)); v = !mmc_send_tuning(mmc, opcode, NULL); @@ -211,7 +359,8 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) } if (ranges[0].start == 0 && ranges[0].end == priv->num_phases - 1) { - clk_set_phase(priv->sample_clk, priv->default_sample_phase); + rockchip_mmc_set_phase(host, true, priv->default_sample_phase); + dev_info(host->dev, "All phases work, using default phase %d.", priv->default_sample_phase); goto free; @@ -248,12 +397,10 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) middle_phase = ranges[longest_range].start + longest_range_len / 2; middle_phase %= priv->num_phases; - dev_info(host->dev, "Successfully tuned phase to %d\n", - TUNING_ITERATION_TO_PHASE(middle_phase, priv->num_phases)); + phase = TUNING_ITERATION_TO_PHASE(middle_phase, priv->num_phases); + dev_info(host->dev, "Successfully tuned phase to %d\n", phase); - clk_set_phase(priv->sample_clk, - TUNING_ITERATION_TO_PHASE(middle_phase, - priv->num_phases)); + rockchip_mmc_set_phase(host, true, phase); free: kfree(ranges); @@ -287,6 +434,8 @@ static int dw_mci_rk3288_parse_dt(struct dw_mci *host) host->priv = priv; + priv->internal_phase = false; + return 0; }